First brew, using Mr. Beer's American Porter hopped LME. It's been fermenting for 7 days, and the aroma has changed from yeasty to more like alcohol and kinda sweet smell, like Robitussin cough syrup. Is this OK, or is it a sign that my batch is tainted? I plan to taste it in a week or two, before bottling, and if it's still too sweet, can I dry hop it for a week or so to balance it better? I like malty beers, and don't care for hoppy ones like IPA, so I wouldn't want to make it too hoppy, so maybe I'll like it the way it is after bottling and conditioning?

Take a hydrometer reading, taste the sample. In a week take another reading to see where your fermentation is at and how the flavor has progressed. When you take a sample for specific gravity drinik it or toss it. To put the sample back in the fermenter would risk infection.

It is OK to taste after a week. I think it's OK to taste every few days - really gives you a personal sense of what's happening. Make sure your dip tube is sanitized - and take a dip or two out every few days. Take enough to get a gravity reading, them taste it. Do this with a few batches of beer and you will have the kind of experience that can never be replicated by reading answers in forums. Don't sweat the Aroma - be patient - taste and see - be patient.

I tasted my first sample today (8 days in fermenter), and it looks, smells, and tastes like (flat) beer! The aroma and flavor of the brew is better than I expected, since the aroma from the fermenter is more like cough syrup. Thanks for your suggestions and moral support!